A Manhattan judge pushed back former President Donald Trump's trial in his New York criminal case, following a surprise shakeup in the case just 10 days before it had been scheduled to begin.

The trial, on felony charges of falsification of business records related to payments to adult film star Stormy Daniels, had been expected to start March 25, but that date has now been scrapped. 

Judge Juan Merchan indicated the trial is now scheduled for April 15, delaying it by 20 days. Manhattan District Attorney Alvin Bragg on Thursday consented to a delay of at least 30 days, and Trump had requested up to 90.

The delay comes after Trump's attorneys protested the late production of a voluminous amount of pretrial discovery in the case. More than 100,000 pages of documents were turned over to Bragg's office by the federal Department of Justice on March 4 and March 13 — and Bragg said another 15,000 pages were slated to be produced March 15.

Merchan wrote that a hearing on the dispute would be held on March 25, the day jury selection had been scheduled to begin in the trial.

"There are significant questions of fact which this court must resolve," Merchan wrote.

"Trial on this matter is adjourned for 30 days from the date of this letter," Merchan wrote in a letter to the attorneys on both sides, dated Friday, March 15. "The court will set the new trial date, if necessary, when it rules on Defendant's motion following the hearing."

Bragg said his office had requested some of the material last year from the U.S. Attorney for the Southern District of New York, and was denied. But Trump's attorneys subpoenaed the documents in January, leading to the late receipt of the material. In filings Thursday and earlier in March, they harshly criticized Bragg's office, accusing it of "being derelict" and of not sufficiently explaining the steps it took to obtain the records.

A representative for the U.S. attorney declined to comment, as did an attorney for Trump and a spokesperson for Bragg.